Pneumatic piano.



W. G. BETZ.

PNEUMATIG PINO, APPLICATION FILED FEB. 2, 1911.

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WITNESSES:

Om-mx) -tmrrnr) sfrarns PATENT oFFIon.

WILLIAM Gr. BETZ, OF CHICAGO HEIGHTS, ILLINOIS, ASSIGNOB. TO STEGER & SONS PIANO MANUFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION.

PNEUMATIC PIANO.

1,012,31 'Y Specification of Letters Patent.

rApplication filed. February 2, 1911. Serial No. 606,221.

To all whom 'it may concern.' cated between the plates 10 andy 20. d'llie Y Be it known that I, WILLIAM Gr. Bn'rz, a citizen of the United States, and a resident of Chicago Heights, county of Cook, and State of Illinois, have invented a certain useful Pneumatic Piano; and I do hereby declare that the -ollowing is a full, clear, and exact description thereof, reference being had to the accompanying drawings.

The object of this invention is to improve the construction of power pneumatics for pneumatic pianos, with particular reference to the location of the primary valve and pouch in relation to the remaining parts ot the power pneumatic and also other features which will be understood from the accompanying drawings and the' following descriptionA and claims:

In the drawings Figure 1 is a central vertical section longitudinally through the power pneumatic in normal position, parts being broken away. Fig. 2 is a similar view showing the positions ot parts when in operation.

A stationary plate 10 extends transversely across the piano. Upon it a bottom plate 11 ot the bellows 12 is secured, the remaining portion of the rear wall of said chamber 26 is forme an impervious, adhesive strip secured to the rear 10, 11 and 12. The screws 23 are stationary in the plate 10 and project into holes in the plate 20 and the nuts 22 screw on the screws Q3 and bear against the plate 20 to space it away from the plate 10 in order to give the suction chamber 26 the desired depth 'or the purpose hereinafter explained.

The suction chamber 26 is in communication with an exhausting means, not shown,

this art. In the underside ot the plate 1() there is a pouch chamber 30 in communication with the tracker boa-rd or' the piano, not shown, through a tube 31. A bleed hole 32 extends from the horizontal portion of the tube 81 down to the suction chamber 26. The open, lower side of the chamber 30 is closed by a primary pouch'. A primary valve 34 is located below said pouch and is a double valve, consisting of valve heads on the upper and lower ends. The length of this stem slightly exceeds the thickness of the plate 2O and tits in a hole or air passageway 85 through the'plate 20 which is of larger diameter than the stem of the valve. A horizontal air chamber 36 is located in the plate 20 in communication with the air passageway 35 and the chamber 36 is in communication with that portion of bellows consisting of the top hinged plate 12 and the flexible intermediate casing 13. An arm 14 projects from the upper Jlorward portion of the plate 12 and is engaged by a rod 15 which extends through a hole in the arm 14 with adjusting nuts 16 and 1i on said rod 15. The rod 16 extends down to a lever or' other means tor operating the piano action, which, however, is not here shown. y

Below the fixed plate 10 there is an adjustable plate 20 extending across the piano parallel substantially with the plate 10 and spaced therefrom by a bar 21 at the front and nuts 22 on screws 23-near the rear and at the ends of the plates 10 and 20. The bar21 is secured to the plate 10 and screws 2li extend through the plate 2O into the bar 21 and an impervious cloth strip 25 covers said parts along the front to render the same air tight for the suction chamber 26 is losurface of the plate 2O which lies below the secondary pouch 38. A stem 39 extends upwardly from the secondary pouch through the chamber 26 and into engagement with the cup-shaped lower end cfa stem40 of a vvalve 41 which lies in a chamber 12in 'the upper surface of the plate 10 and adjacent the plate 11 or" the bellowsfand in communication with the bellows chamber through a passageway plate 11. A passageway 44 extends through the portion of the lplate 10 which lies be- 15 is formed in the lower surfaceY of the Patented Dec. 19, 1911..v

27 which is surfaces of the parts 20,"

but which is familiar to all acquainted with tween the chambers 26 and 42. An air portl a stem` vwith the secondary pouch chamber 37 in the upper 43 which extendsthrough the andfthe air on 34 as and 26j lifts the primary valve and closes the passageway 35, chamber 36 and chamber 37,

communication between the .Y controlled passageway and and sensitive'f in action and *vice also compact. "structitm:enables the l dustby vlSa1d"chamber and w l turn to its normal position. It is thus seen that the primary valve is located in a ver- 35` ,suction chamber and power ,l awhile the device is idle,

` the primary valve down,

nix-primary valve is up,

factionl 4'lll-iis is promoted by the air outlet port from "the 'bellows secondary vl'alve so that said valve accomclosing it. Both the .primary and secondary vplate 1l of the bellows in position to be 'y bellows which renders the construction comclosed by the secondarysvalve 41 when it pact and direct and quick in action.

is up. By reason of the adjustabillty ot the plate parts normally are in 2O all of the primary valves can be simultaneously adjusted in their relation to the primary pouches or, in other words, the suction chamber 26 can be adjusted throughout its entire lengthby one adjustment. This is accomplished by removing the lower part of theclothx'strip 27 from the rear surface of the plate 20, turning the nuts 22 to accomplishdhe desired adjustment, and then replacing the strip 27. Heretofore, so far Vas lfv am aware, it has been necessary to separately adjust each of the primary valves and since their number is very great, it has been a source of considerable trouble and labor.

1I claim as my invention:

1. In a pneumatic piano, plates extending transversely a primary valve in the lower ondary valve in the upper plate, a pouch for each valve located in the plate opposite the plate -in which the valves are located, and means for adjusting the space between said plates.

2. In a pneumatic piano, plates extending transversely of the piano, a primary valve in the lower plate, a secondary valve in the upper plate, a pouch for each valve located in the plate plate in which the valves are located, a ilexible wall connecting said plates, and means for adjusting them with reference to each other.

3. In a pneumatic piano a bellows with an air passageway throu'gh the lower wall thereof and another air passageway in the lower wall of the bellows leadinv to the outer air, a pair of plates below said bellows .and spaced apart to form a suction chamber between them, an air chamber in the upper surface of the upper one of said plates which is in communication with the air passageway in the bellows and said passageway to the outer air, a reduced passageway between said chamber and the suction chamber which is below the passage to said outer air, and a secondary valve controlling a port leading' into said air chamber and between the air passageway thereto from the suction chamber and the passage to the outer air, whereby the former will be clos/ed by the secondaryvalve when it is down and the latter passage closed thereby when it is open.

Ina pneumatic piano a pair of plates extending transversely thereof which are spaced apart to lform a suction chamber, one of said plates bei-ngjixed and the other adjustable with relation to said fixed plate, and primary valves mounted in the adjustable plate, whereby all of the primary valves may be simultaneously adjusted.

5. In a pneumatic piano a pair of plates In operation the the position shown inlilig. 1. When a tube 3l registers with an opening in the tracker board, and outside air enters throug'hjfthe tube 31, it actuates the primary pouch 30 which pushes the primary valve down in the posit-ion shown in Fig. 2, and the passageway-35 is open and it is in communication with the ppuch chamber 37 directly through the chamber 36 so thatf'said secondaryf. pouch 'isactuated by the external air pressure andthe secondary valve 41 lifted sofajsjto clse the air port 45 and open the passageway 44, whereby the air is eX- hausted'-from` the bellows through the passageways 43, 42 and 44 and the chamber 26, and, thereby the bellows is actuated by the external air pressure.

TVhen the tube'3l ceases to register with theOp'ening in the tracker board, and the air is/drawnlslightly from the primary pouch chamber- 30 through the bleed hole 32 so that saidv pouch returns to its upper position against suction in 30 two parallel of the piano,

two parallel it will return the secondary pouch, whereby the secondary valve descends and opens the airfport-45 which permits the bellows to reti'cal position and that the primary pouch is iover the valve so that no dust can enter the pneumatic, for gravity will hold closing the passageway 35 and when it is in use and the i the passageway 35 is also closed. Furthermore, there is directprimary valve the secondary pouch chamber which greatly simplifies the apparatus and renders it extremely quick makes the de- Furthermore, this conbleed hole to be in the ,wall abo-vevfthe suction chamber 26 so that the bleed hole will not become filled with reason of any dust which enters hen any air' passes thjro'u'g'lgl Athe bleed hole to said chamber 26, it tendst't clear the bleed hole rather than lill it withdust. Also the bellows forms the top of thef air chamber for the secondary valve which, renders the construction very simple-,and compact and quick and direct in being also above the plishes the "double function of opening and valves and pouches are located beneath the plate, a sec.

opposite the extending transversely of the piano and spaced apart to form a suction chamber, primary valves mounted inu the lower one of said plates,- and means for adjusting said lower plate with relation to lche upper plate in order to simultaneously adjust the position of said valves. Y

In witness whereof, I have hereunto affixed my signature 4in the presence of the H. C. WEBLAN, OLGA PETERSON. 

